Allow sparc64 to fail on CI

Author: alexcrichton

.travis.yml

@@ -24,6 +24,8 @@ matrix:
   allow_failures:
     # FIXME(#987) move back to include once 404 is fixed
     - env: TARGET=s390x-unknown-linux-gnu
+    # FIXME(#1064)
+    - env: TARGET=sparc64-unknown-linux-gnu
   include:
     # 1.13.0 compat
     - env: TARGET=x86_64-unknown-linux-gnu NO_ADD=1